Method and apparatus for applying decorative coating to a substrate

ABSTRACT

A METHOD AND APPARATUS ARE DISCLOSED WHEREIN A QUANTITY OF PIGMENTED COATING MATERIAL IS PLACED ON THE SURFACE OF A POOL OF SUPPORTING LIQUID, AND A PORTION OF THE POOL, WITH THE COATING MATERIAL ENTRAINED, IS DRAWN OFF AND PERMITTED TO FLOW OVER A SUBSTRATE. EXCESS LIQUID OF THE DRAWN OFF PORTION RUNS OFF, AND THE COATING MATERIAL REMAINS ON THE SUBSTRATE. THE METHOD CAN BE PERFORMED ON A CONTINUOUS BASIS, THE POOL BEING A MOVING, CONTINUOUSLY REPLENISHED BODY OF LIQUID, AND THE STRIP TO BE COATED BEING MOVED CONTINUOUSLY PAST A POSITION WHEREIN THE DRAWN OFF PORTION OF THE SUPPORTING LIQUID AND THE ENTRAINED COATING MATERIAL ARE APPLIED THERETO.

June 1972 K. M. ROSENBERG METHOD AND APPARATUS FOR APPLYING DECORATIVE COATING TO A SUBSTRATE Filed Jan. 9, 1970 ATTORNEYS.

6 mn um NGQ. W W fi m Mw|. 1 1 1 Val/K? w. M M 9 m 8 M m W w m N\ Q\ A. A $3 United States Patent "ice US. Cl. 117-39 9 Claims ABSTRACT OF THE DISCLOSURE A method and apparatus are disclosed wherein a quantity of pigmented coating material is placed on the surface of a pool of supporting liquid, and a portion of the pool, with the coating material entrained, is drawn off and permitted to flow over a substrate. Excess liquid of the drawn off portion runs off, and the coating material remains on the substrate. The method can be performed on a continuous basis, the pool being a moving, continuously replenished body of liquid, and the strip to be coated being moved continuously past a position wherein the drawn 01f portion of the supporting liquid and the entrained coating material are applied thereto.

This invention relates to a method and apparatus for applying a decorative coating to a substrate. More particularly, this invention relates to a method and apparatus wherein pigmented material floating on-a body of supporting liquid is applied to a substrate while flowing under the influence of gravity.

Substrate as used herein is meant in a broad sense to mean any sheet or web-like material capable of bearing a surface design. The present method and apparatus are believed to have their greatest utility when used in connection with flexible substrates, such as woven and non-Woven textiles, paper, and extruded, rolled or cast plastic polymeric materials such as sheet polyvinyl chloride. The utility of the present method and apparatus is not limited, however, to use with flexible substrates. Thus, it is within the purview of this invention to apply decorative coatings to rigid substrates, such as rigid plastic polymeric sheets, high pressure laminates, wood veneer or plywood, cardboard, chipboard, or the like.

Decorative pigment patterns have heretofore been applied to substrates by means of a wide variety of methods and apparatus. The present method and apparatus, however, provide a unique decorative effect, not obtainable on a predictable and repetitive basis by any method and apparatus heretofore known.

In view of the foregoing, it is an object of this invention to provide a method and apparatus for applying a decorative coating to a substrate.

It is another object to provide a method and apparatus whereby pigmented material may be applied to a substrate to obtain a repetitive characteristic pattern.

It is another object to provide an apparatus whereby the method may be practiced on a continuous basis.

Other objects will appear hereinafter.

The foregoing and other objects are realized, in a presently preferred form of the invention, by a method involving the steps of placing a quantity of pigmented coating material on the surface of a pool of supporting Patented June 20, 1972 liquid. A portion of the pool is drawn OH with the coating material entrained, and the drawn off portion and entrained coating material applied to a substrate. In accordance with the method, the coating material entrained with the drawn ofi portion remains on the substrate in a characteristic pattern, while the excess supporting liquid is permitted to run off. The coating material may be manipuated while on the surface of the pool to provide a desired decorative pattern, transferable to the substrate. Alternatively, the coating material may be entrained with the drawn off portion of the supporting liquid in a configuration determined primarily by the technique used to apply it to the support liquid.

The manner in which a portion of the support liquid and entrained coating material are drawn oif from the pool account, in large measure, for some of the unique decorative effects obtainable with the present method: A top layer of the pool, together with the coating material thereon are permitted to spill, as a thin film, down a sloped plate on to the substrate. Acceleration of the material on the sloped plate accounts for a stretching and convoluting effect on the coating material, and results in a characteristic decorative pattern not easily obtainable by any other known method.

The present method can be performed on a continuous basis by making the pool a continuously moving body of support liquid, and by continuously placing coloring material on the pool. When the method is practiced continuously, the substrate to be coated can be past at a predetermined rate through a station wherein it receives the drawn oft" support liquid and coloring material from the pool.

In another of its aspects, the invention comprises an apparatus for practicing the foregoing method. Such apparatus includes, in a presently preferred form, a tank for retaining a body of supporting liquid, means associated with the tank for applying to the supporting liquid a quantity of pigmented coating material and means associated with the tank for removing a portion of the support liquid with the coating material entrained. The last-mentioned means may take the form of a weir, and an angled movable surface or wall, down which the removed portion of the support liquid and entrained coating material may fall as a thin film. A support is provided adjacent a lower edge of the wall for the substrate material.

For the purpose of illustrating the invention, there is shown in the drawings a form which is presently preferred; it being understood, however, that this invention is not limited to the precise arrangements and instrumentalities shown.

FIG. 1 is a side elevation view of an apparatus in accordance with the present invention.

FIG. 2 is an end elevation view of the apparatus in FIG. 1.

FIG. 3 is an illustration of one representative pattern of the sort obtainable with the present method and apparatus.

Referring now to the drawings in detail, wherein like numerals indicate like elements, there is seen in FIG. 1 an apparatus, designated generally by the reference numeral 10. 4

The apparatus includes a tank 12 for retaining a body 14 of liquid. The tank 12 may be supported by legs 16, 18 or the like in a conventional manner.

The illustrated apparatus 10 is suitable for performing the present process on a continuous basis, and for this purpose, is provided with spaced baflles or weirs 20, 22 adjacent its respective ends. Support liquid 14 is introduced to the tank 12 through a conduit 24 associated with a pump 26. The liquid 14 flows over the baflle or weir 20, along a major portion of the length of the tank 12, and then over the baflle or weir 22.

A downwardly extending trough-like wall 30 is pivotably coupled, in the illustrated embodiment, to an end of the tank 12 adjacent the baflle 22, and has a width generally coextensive with the width of the tank 12. Material flowing over the bafile 22 thus exits the tank 12 by flowing downwardly as a thin film along the wall 30. A mechanical actuator, such as the illustrated fiuid cylinder 32 serves to pivot the wall 30 through a desired arc, for a purpose to be explained later.

A support surface 34 is disposed adjacent a lower edge 36 of the Wall 30. As is apparent in FIG. 1, the support surface 34 has a cross-sectional shape including an apex portion 38 and intersecting angled surfaces 40 and 42 extending downwardly away from the apex portion 38.

Associated with the tank 12 is a dispenser 44 whereby a quantity of pigmented coating material 46 may be applied to the surface of the liquid body 14. The dispenser 44 may take any suitable form. For example, referring to FIG. 2, the dispenser 44 may include a hopper 48 for storing coating material, and a series of nozzles 50 associated with the hopper and spaced across the width of the tank 12 for applying the material to the surface of the liquid body 14.

The nozzles 50 lay stripes of coating material on the surface of the liquid body 14. Such stripes may be continuous, or if desired, intermittent.

Referring again to FIG. 1, means may be provided in the tank 12 for manipulating the coating material 46 on the surface of the liquid body 14 to provide a desired pattern. Such means may take the form of an endless belt 52, disposed transversely with respect to the tank 112, and supported on spaced pulleys 54 and 55. The belt 52, as is best seen in FIG. 2, includes upwardly extending projections 56 of suflicient height to engage a bottom surface of the coating material 46. A motor 58, drivingly coupled to one of the pulleys 54, 55, drives the endless belt '52 to move the projections 56 transversely with respect to the tank 12. Thus, the configuration of the coating material 46 on the surface of the liquid body 14 can be selectively altered through the use of the above-described manipulating means. It should also be apparent that manipulating means other than the specific form illustrated can be used to obtain other desired configurations of the coating material, and that the manipulating means can be omitted entirely, if desired.

The surface layer of the liquid body 14, together with the entrained coating material 46 thereon passes over the weir 22 and across the surface of the wall 30. Acceleration of the thus drawn off portion of the liquid body 14 produces in the coating material a characteristic elongation and stretching effect which, when transferred to a substrate, is highly decorative.

Transfer is accomplished in the illustrated form of the apparatus, by passing an endless substrate across the support surface 34 in juxtaposition to the lower edge 36 of the wall 30. A stand 62 is provided for a roll 64 of the material forming the substrate 60. Wind-up means, not shown, draw the substrate 60 from the roll 64 at a predetermined rate correlated with the rate of How of the support liquid of the body 14. The support liquid and entrained coating material 46 flow downwardly along the wall 30 into contact with the substrate 60 and across its face. The support surface 34 imparts to the substrate 60 the pitch necessary to maintain the desired flow. The coat- 4 ing material 46 remains on the substrate 60, but excess support liquid drains from the substrate 60 and support surface 34 into overflow troughs 66 and 68. The liquid may then be filtered, and re-cycled to the pump 26 through the diagrammatically shown conduit 70.

Referring to FIG. 3, there is seen a representative substrate 60 coated in accordance with the present method and apparatus. Clearly seen is a bias effect due to the relative motion of substrate 60 and the support liquid and coating material passing along the wall 30. The coating material 46 assumes a characteristic shading, giving a three-dimensional effect, due to stretching and convoluting of the coloring material 46 as it accelerates and decelerates with the support liquid as it exits the tank 12 and traverses the wall 30. Different effects may be obtained by use of the actuator 32 to position the wall 30 with respect to the apex portion 38. Thus, by positioning of the lower edge 36 of the wall with respect to the apex portion 38, symmetrical or assymetrical patterns may be placed on the substrate 60.

In practicing the present invention, the support liquid 14 and the coating material 46 should be immiscible, the density of the support liquid being in excess of that of the coating material 46. In one operative form of the invention, the coating material 46 was a vinyl paint comprising 250 ml. red vinyl resin concentrate [sold under the trademark Sirascreen by Alfa Ink and Chemical Co.], ml. vinyl thinner comprising /3 naphtha and /3 isophorene, and a further 24 ml. isophorene. The support liquid 14 was water.

The present invention may be embodied in other specific forms without departing from the spirit or essential attributes thereof.

I claim:

1. A method of applying a decorative coating to a substrate comprising the steps of placing a quantity of pigmented coating material on the surface of a pool of supporting liquid to form a pattern, said supporting liquid being immiscible with and capable of floating on its upper surface said pigmented coating material, dravn'ng off a surface layer of said pool of supporting liquid with said coating material entrained therewith, allowing said drawn olf supporting liquid and coating material to spill down an inclined wall as a thin film, thereby accelerating and convoluting said coating material, positioning a substrate to be coated beneath the lower edge of said wall to receive said drawn off supporting liquid and coating material, said substrate being so oriented that excess supporting liquid runs off said substrate, leaving a decorative coating of said pigmented coating material on said substrate.

2. A method according to claim 1 wherein said substrate comprises a flexible material.

3. A method according to claim 1 wherein said coating material is entrained with said surface layer of supporting liquid in a configuration similar to its configuration just prior to said drawing off step.

4. A method according to claim 1 wherein said supporting liquid is water.

5. A method according to claim 1 wherein said pigmented coating material is manipulated on the surface of said pool of supporting liquid to impart a desired configuration thereto prior to being drawn off with said surface layer of supporting liquid.

(6. A method according to claim 1 wherein said surface layer of supporting liquid and coating material are drawn ofi? over a weir before spilling down said inclined wall.

7. A method according to claim 1 wherein said method is carried out continuously at a predetermined rate, and said step of positioning a substrate to receive said drawn off supporting liquid and coating material includes passing a continuous substrate beneath the lower edge of said inclined wall at a predetermined rate.

8. A method according to claim 7 wherein said continuous substrate passes beneath the lower edge of said inclined wall in a direction generally transverse to the 5 6 direction of flow of said supporting liquid and coating 2,140,498 12/ 1938 Dreyer 117-39 material. 1,931,667 10/ 1933 Loetscher 117-39 9. A method according to claim 7 wherein said continuous substrate comprises a flexible material and is ALF-RED V Prim y E i oriented with its central longitudinal portion raised and 5 R ESPOSITO Assistant Examiner its lateral edge portions sloping downwardly therefrom at least while passing beneath the lower edge of said inclined wall. 117-37 R, 102 PC References Cited UNITED STATES PATENTS 10 1,930,036 10/1933 Bracewell 117-39 3,293,063 12/1966 Pohl et a1 117-39 

